Disfunção ventricular esquerda em hamsters com doença de Chagas tratados com etanercept / Left ventricular dysfunction in hamsters with Chagas disease and treated with etanercept

Objetivo: a doença afeta mais de 10 milhões de pessoas na América Latina. Leva a cardiomiopatia dilatada inflamatória em 30% dos pacientes como conseqüência tardia da infecção pelo protozoário Trypanosoma cruzi, com pior prognóstico que as outras cardiomiopatias dilatadas. estudos prévios mostram aumento dos níveis circulantes do fator de necrose tumoral-alfa (TNF-x) em pacientes com cardiomiopatia chagásica crônica. Assim, o objetivo do presente trabalho foi avaliar efeito do bloqueio do TNF-x com Etanercept na função ventricular esquerda em hamsters sírios cronicamente infectados pelo T. cruzi...

Reference values from M-mode and Doppler echocardiography for normal Syrian hamsters.

AIMS: Echocardiography has recently been introduced to small animal research, allowing serial measurements of cardiac diseases. In addition, the hamster model has been increasingly used, as it mimics many human heart conditions. However, no reference range of echocardiographic values reflecting normal left ventricular (LV) function exists for hamsters. The purpose of this study was to provide one. METHODS AND RESULTS: The study group consisted of 118 10-week-old, female, Syrian golden hamsters, which underwent high-resolution echocardiography. LV mass was calculated using the corrected cube formula, and LV systolic and diastolic function were assessed by fractional shortening and mitral inflow pulsed-wave Doppler, respectively. The myocardial performance index (MPI) measured the time spent in isovolumic activity and reflected both systolic and diastolic function. The mean+/-SD LV mass, fractional shortening, and MPI were 0.19+/-0.04 g, 44.7+/-6.6%, and 0.39+/-0.1, respectively. E and A waves were differentiated in 52% of all animals. Logistic regression adjusted with a cutoff of 378 bpm revealed that the risk of E/A wave fusion was 35 times greater (95% CI: 12.6; 98.4) in animals with a heart rate >378 bpm. CONCLUSION: This study documents echocardiographic characteristics in normal Syrian hamsters, which can be used as control values for future studies.